Gantry crane for transporting track panels

ABSTRACT

A gantry crane for transporting track panels comprises a longitudinal beam extending in a longitudinal direction. The longitudinal beam includes lifting tools for gripping a track panel and is supported by chassis frames including in each case two vertical beams, having vertical adjustment drives, and two transverse beams connected to the vertical beams. The transverse beams extend perpendicularly to the longitudinal direction and have drives for transverse adjustment. Pairs of crawler tracks are fastened to the chassis frames for mobility of the longitudinal beam, each crawler track being connected to one of the vertical beams. Each chassis frame is designed to be rotatable relative to the longitudinal beam by means of a vertical axis of rotation which is disposed centrally between the two crawler tracks and connects the two transverse beams to the longitudinal beam.

CROSS REFERENCE TO RELATED APPLICATIONS

Applicants claim priority under 35 U.S.C. §119 of AUSTRIAN ApplicationNo. AT A1953/2004 filed on Nov. 22, 2004. Applicants also claim priorityunder 35 U.S.C. §120 of International Application No. PCT/EP2005/009635filed on Sep. 8, 2005. This application is a by-pass continuationapplication of said International Application No. PCT/EP2005/009635filed on Sep. 8, 2005. The International application under PCT Article21(2) was not published in English. The disclosure of the aforementionedInternational application and Austrian application are incorporated byreference herein.

BACKGROUND OF THE INVENTION

1. Field of the invention

The invention relates to a gantry crane. More particularly, theinvention relates to a gantry crane for transporting track panels,comprising a longitudinal beam extending in a longitudinal direction andhaving lifting tools for gripping a track panel. The longitudinal beamis supported by chassis frames. Each chassis frame includes verticalbeams, having vertical adjustment drives, and transverse beams connectedto the vertical beams. The transverse beams extend perpendicularly tothe longitudinal direction and include drives for transverse adjustment.Pairs of crawler tracks are fastened to the chassis frames for mobilityof the longitudinal beam, each crawler track being connected to one ofthe vertical beams.

2. The Prior Art

EP 0 505 240 A1 shows a gantry crane for transporting track panels. Thisgantry crane comprises a gantry frame which is mobile with the aid offour vertically adjustable crawler tracks. Lifting tools spaced from oneanother in the longitudinal direction of the frame are arranged on thegantry frame for gripping the track panel. In addition, verticallyadjustable flanged rollers are provided by means of which the gantrycrane is also mobile on a railroad track.

DE 2 309 930 A1 shows a gantry crane for laying track panels, comprisinga carrying device for gripping the track panel to be transported. Thegantry crane has vertically and laterally adjustable crawler tracks aswell as vertically adjustable lifting rams arranged at either sidethereof. Several of these gantry cranes are driven onto the laid-downtrack panel via flanged rollers and connected to the track panel bymeans of corresponding lifting tools. Subsequently, the track panel israised by lowering the lifting rams onto the ballast bed, and thecrawler track is lowered onto the ballast bed by lateral and verticaladjustment underneath the track panel. After all four lifting rams haveat last been raised, the track panel is moved into the construction gapwith the aid of the crawler tracks.

A track maintenance machine for exchanging a track panel is known fromDE 33 40 739 A1. This track maintenance machine consists essentially ofan elongated beam which, at the ends thereof, may be selectivelysupported on an on-track undercarriage or on a crawler track.

SUMMARY OF THE INVENTION

It is the primary object of this invention to improve a gantry crane ofthe first-described type so that optimal maneuverability is assured evenunder spatially constricted conditions.

This object is accomplished in accordance with the invention with agantry crane for transporting track panels which comprises alongitudinal beam extending in a longitudinal direction. Thelongitudinal beam includes lifting tools for gripping a track panel andis supported by chassis frames including in each case two verticalbeams, having vertical adjustment drives, and two transverse beamsconnected to the vertical beams. The transverse beams extendperpendicularly to the longitudinal direction and have drives fortransverse adjustment. Pairs of crawler tracks are fastened to thechassis frames for mobility of the longitudinal beam, each crawler trackbeing connected to one of the vertical beams. The present inventionprovides that each chassis frame is designed to be rotatable relative tothe longitudinal beam by means of a vertical axis of rotation disposedcentrally between the two crawler tracks and connecting the twotransverse beams to the longitudinal beam.

As a result of this structurally relatively simple configuration,mobility of the gantry crane is significantly improved, so that thepicked-up track panel may be transported without problems alsotransversely or even obliquely to the longitudinal direction of thetrack. In this context, it is of particular advantage that the stabilityof the frame is not compromised in any way. The chassis frame ismaneuverable very simply by means of variable actuation of the motivedrives.

BRIEF DESCRIPTION OF THE DRAWINGS

Other benefits and features of the present invention will becomeapparent from the following detailed description considered inconnection with the accompanying drawings. It is to be understood,however, that the drawings are designed as an illustration only and notas a definition of the limits of the invention.

In the drawings, wherein similar reference characters denote similarelements throughout the several views:

FIG. 1 shows a side view of a gantry crane;

FIG. 2 shows a cross-section according to section line II in FIG. 1; and

FIG. 3 shows a schematic top view of the gantry crane.

DETAILED DESCRIPTION OF THE DRAWINGS

Referring now in detail to the drawings, FIGS. 1 to 3 show a gantrycrane 1 which comprises a central longitudinal beam 5. Said beam extendsin a longitudinal direction 2 and is connected by means of two chassisframes 24 to crawler tracks 4. Each chassis frame 24 is formed by twovertical beams 20 and two transverse beams 6, the latter extendingperpendicularly or at an angle to the longitudinal direction 2. Eachchassis frame 24 is designed to be rotatable relative to thelongitudinal beam 5 by means of a vertical axis of rotation 25 which isarranged centrally between the two crawler tracks 4 and connects the twotransverse beams 6 to the longitudinal beam 5.

As can be seen in FIG. 3, a maximum angle of rotation α±15° of thechassis frame 24 with respect to the longitudinal direction 2 of thelongitudinal beam 5 is possible. The axis of rotation 25 extendsperpendicularly with regard to the longitudinal direction of the twotransverse beams 6.

Power sources 7 are fastened to the longitudinal beam 5, consistingessentially of an internal combustion engine and a hydraulic pump. Inaddition, guide members 8, spaced from one another in the longitudinaldirection of the frame, are vertically adjustably mounted on thelongitudinal beam 5 and connected in each case to drives 9 for verticaladjustment. The lower end of each guide member 8 is connected to ahorizontally extending beam 10 which, in turn, is connected to twolifting tools 11 spaced from one another in the longitudinal directionof the beam. Each beam 10 is supported on said guide member 8 forrotation about a vertical axis 12. The lifting tools 11 are designed inthe known manner in the shape of clamps or hooks for form-fittinglygripping a rail head or a rail base of a track panel 13 to betransported.

Each of the four crawler tracks 4 consists of two undercarriage units14, 15 which are spaced from one another in the longitudinal directionof the frame, or rather in the longitudinal direction 2 of thelongitudinal beam 5. Both undercarriage units 14, 15 are connected toone another in each case by means of a chassis beam 17 mounted on thevertical beam 20 for pivoting about a horizontal axis 16 extendingperpendicularly to the longitudinal direction of the frame. Eachundercarriage unit 14, 15 is in turn mounted on the chassis beam 17 forpivoting about a horizontal undercarriage axis 18 extendingperpendicularly to the longitudinal direction of the frame. Associatedwith each undercarriage unit 14 or 15, designed as crawler tracks 4, isa separate motive drive 19.

The two horizontal undercarriage axes 18 of the two undercarriage units14, 15 are arranged spaced from one another at a distance of about 2.5to about 3.5 meters, preferably 3 meters. As visible particularly inFIG. 2, two drives 9 are fastened to the longitudinal beam 5 forvertical adjustment of each guide member 8, respectively. Verticaladjustment drives 3 are arranged inside the two-part vertical beams 20,the latter being telescopically extendable in the vertical direction.

As can be seen in the left-hand half of FIG. 2, the lower ends of two ofthe vertical beams 20 at a time, adjustable in the vertical directionand associated in each case with a crawler track 4, are connected to oneanother by means of a connecting beam 21. The said chassis beam 17 isfastened to the connecting beam 21 for pivoting about the horizontalaxis 16. The respective upper halves of the two two-part vertical beams20 are connected to a guide tube 22 which is displaceably mounted withinthe transverse beam 6. With the aid of a transverse adjustment drive 23,the guide tube 22, together with the vertical beams 20 and theassociated undercarriage units 14 and 15, is adjustable in thelongitudinal direction of the transverse beam 6.

In working operations for removing a track panel 13, the gantry crane 1is moved forward with the aid of the crawler tracks 4 on the region ofthe ballast bed or the earth formation laterally adjoining the laidtrack, until the construction gap is reached. Subsequently, thelongitudinal beam 5 together with the transverse beams 6 is lowered bymeans of corresponding actuation of the vertical adjustment drives 3.The drives 9 are then actuated until the lifting tools 11 come to lieimmediately above the rails of the track panel 13 to be gripped. Afterthe said lifting tools 11 have been form-fittingly engaged with theassociated rail, the track panel 13 is lifted by actuation of thevertical adjustment drives 3 and the drives 9 (see FIG. 1).

By actuation of the motive drives 19, the raised track panel 13 can nowbe transported away. During this, better adaptation to an uneven ridingsurface is ensured due to the special design and mounting of the crawlertracks 4, in which the individual undercarriage units 14, 15 arepivotable about both the undercarriage horizontal axis 18 and thehorizontal axis 16. The expression “horizontal” refers to that situationin which the gantry crane 1 is resting on a horizontal plane.

Accordingly, while an embodiment of the present invention has been shownand described, it is obvious that many changes and modifications may bemade thereunto without departing from the spirit and scope of theinvention.

1. A gantry crane for transporting track panels, comprising: a) alongitudinal beam extending in a longitudinal direction and havinglifting tools for gripping a track panel; b) chassis frames supportingthe longitudinal beam, each chassis frame including: 1) two verticalbeams; 2) two transverse beams connected to the vertical beams andextending perpendicularly to the longitudinal direction; 3) verticaladjustment drives associated in each case with the vertical beams; 4)drives for transversely adjusting the transverse beams; 5) pairs ofcrawler tracks fastened to the chassis frame for mobility of thelongitudinal beam, each crawler track being connected to one of thevertical beams; and 6) a vertical axis of rotation, disposed centrallybetween the two crawler tracks and connecting the two transverse beamsto the longitudinal beam, for allowing rotation of the chassis framerelative to the longitudinal beam.